Viewer Experience of Obscuring Scene Elements in Photos to Enhance Privacy

Hasan, Rakibul; Hassan, Elham A.; Li, Yifang; Caine, Kelly; Crandall, David J.; Hoyle, Roberto; Kapadia, Apu

doi:10.1145/3173574.3173621

Cited by 55 publications

(29 citation statements)

References 27 publications

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“…We found that blurring improves quantitiy of recalled details, but does not improve the accuracy of recall. Although blurring for obfuscation is commonly used in research [7,13] and industry (e.g., Google Street View), we cannot make claims about the impact of other techniques on memory recall. We plan to compare in the impact of obfuscation in explicit photo capturing contexts such as taking selfies.…”

Section: Lesson Learnt: Ambiguous Lifelogs Might Distort Memoriesmentioning

confidence: 99%

See 1 more Smart Citation

Can Privacy-Aware Lifelogs Alter Our Memories?

Elagroudy

Khamis

Mathis

et al. 2019

Extended Abstracts of the 2019 CHI Conference on Human Factors in Computing Systems

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The abundance of automatically-triggered lifelogging cameras is a privacy threat to bystanders. Countering this by deleting photos limits relevant memory cues and the informative content of lifelogs. An alternative is to obfuscate bystanders, but it is not clear how this impacts the lifelogger's recall of memories. We report on a study in which we compare viewing 1) unaltered photos, 2) photos with blurred people, and 3) a subset of the photos after deleting private ones, on memory recall. Findings show that obfuscated content helps users recall a lot of content, but it also results in recalling less accurate details, which can sometimes mislead the user. Our work informs the design of privacyaware lifelogging systems that maximizes recall and steers discussion about ubiquitous technologies that could alter human memories.

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Section: Lesson Learnt: Ambiguous Lifelogs Might Distort Memoriesmentioning

confidence: 99%

“…Although previous works (e.g., [7,13]) investigated the impact of obfuscation on privacy protection and user experience, it remains unclear how obfuscation impacts the recall of memories. Closing this gap is crucial as recalling memories is one of the main motivations behind lifelogging.…”

Section: Introductionmentioning

confidence: 99%

Can Privacy-Aware Lifelogs Alter Our Memories?

Elagroudy

Khamis

Mathis

et al. 2019

Extended Abstracts of the 2019 CHI Conference on Human Factors in Computing Systems

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“…The computed blur thresholds and classification rate determine that blur is effective at increasing privacy while retaining utility, but that the trade-off must be evaluated across applications and sensors. Hasan et al [34] investigated various image filters such as masking, blurring, and pixelation with respect to their effectiveness in obscuring specific features of the content as well as retaining the utility and aesthetics of the photograph. They reported that blur was effective at obscuring the gender of the photographed person, though not so much the ethnicity or expression.…”

Section: Introductionmentioning

confidence: 99%

The Security-Utility Trade-off for Iris Authentication and Eye Animation for Social Virtual Avatars

John

Jörg

Koppal

et al. 2020

IEEE Trans. Visual. Comput. Graphics

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The gaze behavior of virtual avatars is critical to social presence and perceived eye contact during social interactions in Virtual Reality. Virtual Reality headsets are being designed with integrated eye tracking to enable compelling virtual social interactions. This paper shows that the near infra-red cameras used in eye tracking capture eye images that contain iris patterns of the user. Because iris patterns are a gold standard biometric, the current technology places the user's biometric identity at risk. Our first contribution is an optical defocus based hardware solution to remove the iris biometric from the stream of eye tracking images. We characterize the performance of this solution with different internal parameters. Our second contribution is a psychophysical experiment with a same-different task that investigates the sensitivity of users to a virtual avatar's eye movements when this solution is applied. By deriving detection threshold values, our findings provide a range of defocus parameters where the change in eye movements would go unnoticed in a conversational setting. Our third contribution is a perceptual study to determine the impact of defocus parameters on the perceived eye contact, attentiveness, naturalness, and truthfulness of the avatar. Thus, if a user wishes to protect their iris biometric, our approach provides a solution that balances biometric protection while preventing their conversation partner from perceiving a difference in the user's virtual avatar. This work is the first to develop secure eye tracking configurations for VR/AR/XR applications and motivates future work in the area.

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“…One approach is to fully or partially obfuscate sensitive imagery (photo/video) elements [55,61,78,105] or user attributes [25,115,117]. Obfuscating attributes, however, may not be effective against inference 4 attacks [25].…”

Section: Obfuscationmentioning

confidence: 99%

“…For example, increasing both the size of masked area and the pixelation level of deterioration led to lower human recognition rates. More recently, Hasan et al [55] weighed users' perception of both privacy and utility of five privacy filters that were applied with a different strength (resulting in a total of 11 filters) to obscure an object in photos. Utility in this context measured the aesthetics and overall user satisfaction with content viewing experience [55].…”

Section: Obfuscationmentioning

confidence: 99%

Investigating Decay Representations for Privacy and Online Reputation Management

Mohamed¹

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The main goal of this thesis is to explore how Online Social Networks (OSNs) can support users in managing their online reputation during important selection processes. More specifically, we look at mechanisms that help social media users automatically dissociate from their past online activities, primarily in a hiring context. I would like to begin by thanking my thesis supervisor, Sonia Chiasson, for her continuous support. She has been a great example and a role model to me, on both a personal and a professional level. She always made herself available and provided unlimited advice. As someone with a high level of knowledge and a broad spectrum of expertise, Prof. Chiasson has given me invaluable guidance throughout the duration of my degree and I am deeply indebted to her. I would also like to thank my defence committee, Pamela Briggs, Daniel Amyot, Audrey Girouard, and Andrew Patrick. They have provided me with useful guidance and valuable feedback that helped inform various parts of the thesis. I am also grateful to my parents and my brothers. I would like to thank them for believing in me and for always encouraging me to achieve my goals. Although they are so far away, they never ceased to give me the emotional support and encouragement I needed. I would not have been able to complete this work without their support. I thank Thaís Bardini Idalino for being dedicated in our collaborative study. I am happy to have worked with such a smart woman. I also thank Khadija Baig for being such a dedicated researcher. I am grateful for her effort and time spent on transcribing interviews in one of the Chapters, and for her emotional support. Similarly, I am grateful to Paulina Chametka for her help in various tasks, including running interviews, audio transcription, and data analysis. I appreciate her time and effort.

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Viewer Experience of Obscuring Scene Elements in Photos to Enhance Privacy

Cited by 55 publications

References 27 publications

Can Privacy-Aware Lifelogs Alter Our Memories?

Can Privacy-Aware Lifelogs Alter Our Memories?

The Security-Utility Trade-off for Iris Authentication and Eye Animation for Social Virtual Avatars

Investigating Decay Representations for Privacy and Online Reputation Management

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